最近50年来莱州湾东部典型砂岸潮上带土地利用变化研究   总被引：3，自引：1，他引：2  

仲少云  王庆  战超  李雪艳  王昕 《海洋与湖沼》2015,46(2):410-419

以不同时期测量和成像的地形图和高分辨率遥感影像为数据源,综合使用野外调查、遥感(RS)、全球定位系统(GPS)和地理信息系统(GIS)等方法,对最近50多年来莱州湾东部砂岸典型岸段(界河口—刁龙嘴)的土地利用变化进行研究。结果表明,最近50多年来,莱州湾东部海岸土地利用/土地覆被变化显著,土地利用类型转化的总趋势是风沙地、林地、耕地向养殖池及居民地转化。从20世纪90年代初以来,该岸段潮上带风沙地大部分已为养殖池(塘、大棚)等所覆盖,在沿海防护林和海域之间新出现了一条平行于岸线、基本连续展布的水产养殖设施带,其外侧建有高出当地最高潮位的防浪堤。潮上带土地覆被的如此深刻变化,必然深刻地改变风暴潮作用时的水动力边界条件,导致风暴潮作用过程中沿水下岸坡—海滩—潮上带方向的能量分布发生调整,进一步会对海岸地貌及冲淤发生的范围、强度、性质和形式等带来变化。因此,大面积的潮上带土地利用可能是莱州湾东部砂岸,最近30年来海岸地貌冲淤演变的重要影响因素之一,这为今后深入研究并预测该段海岸地貌冲淤变化提供了新的视角。  相似文献   

2009-2013年普里兹湾表层水体中生物硅含量的年际变化及其与全球气候事件的关系     

扈传昱  韩正兵  孙维萍  陈际雨 《海洋与湖沼》2015,46(2):285-294

利用中国南极科学考察期间获得的颗粒物样品,对南大洋普里兹湾海域水体中生物硅的含量分布及年际变化情况进行了分析。研究结果显示:在2013年夏季普里兹湾表层水体中生物硅含量在0.38—8.62μmol/dm3之间变化,平均为1.55±1.86μmol/dm3。生物硅在67°S以南湾内区域表层水体中的含量明显高于67°S以北的湾外区域,最大值出现在普里兹湾陆架区,生物因子是表层水体生物硅含量分布的主控因子。根据不同年份即25、26、27、28、29次南极科学考察期间获取的数据研究显示,普里兹湾表层水体中生物硅含量存在明显的年际差异。历史数据分析结果表明,气候事件对普里兹湾海冰变化有明显的影响,因而对相应年份该海域浮游植物数量和种群结构也会产生一定的影响,从而导致表层水体中生物硅含量的年际差异。  相似文献   

Macrobenthos relative to the oxygen minimum zone on the East Indian margin,Bay of Bengal          下载免费PDF全文

Akkur V. Raman  Rayaroth Damodaran  Lisa A. Levin  Thiruchitrambalam Ganesh  Yannamani K. V. Rao  Sateesh Nanduri  Rakhesh Madhusoodhanan 《Marine Ecology》2015,36(3):679-700

The Bay of Bengal remains one of the least studied of the world's oxygen minimum zones (OMZs). Here we offer a detailed investigation of the macrobenthos relative to oxygen minimum zone [OMZ – DO (dissolved oxygen), concentration <0.5 ml·1^?1] at 110 stations off the North East Indian margin (16⁰ and 20⁰ N) featuring coastal, shelf and slope settings (10–1004 m). Macrobenthos (>0.5 mm) composition, abundance and diversity were studied in relation to variations in depth, dissolved oxygen, sediment texture and organic carbon. Using multivariate procedures powered by SIMPROF analysis we identified distinct OMZ core sites (depth 150–280 m; DO 0.37 ml·1^?1) that exhibited dense populations of surface‐feeding polychaetes (mean 2188 ind. m^?2) represented by spionids and cossurids (96%). Molluscs and crustaceans were poorly represented except for ampeliscid amphipods. The lower OMZ sites (DO > 0.55 ml·l^?1) supported a different assemblage of polychaetes (cirratulids, amphinomids, eunicids, orbinids, paraonids), crustaceans and molluscs, albeit with low population densities (mean 343 ind. m^?2). Species richness [E(S₁₀₀)], diversity (Margalef d; H’) and evenness (J’) were lower and dominance was higher within the OMZ core region. Multiple regression analysis showed that a combination of sand, clay, organic carbon, and dissolved oxygen explained 62–78% of the observed variance in macrobenthos species richness and diversity: E(S₁₀₀) and H’. For polychaetes, clay and oxygen proved important. At low oxygen sites (DO <1 ml·l^?1), depth accounted for most variance. Residual analysis (after removing depth effects) revealed that dissolved oxygen and sediment organic matter influenced 50–62% of residual variation in E(S₁₀₀), H’ and d for total macrofauna. Of this, oxygen alone influenced up to ~50–62%. When only polychaetes were evaluated, oxygen and organic matter explained up to 58–63%. For low oxygen sites, organic matter alone had the explanatory power when dominance among polychaetes was considered. Overall, macrobenthic patterns in the Bay of Bengal were consistent with those reported for other upwelling margins. However, the compression of faunal gradients at shallower depths was most similar to the Chile/Peru margin, and different from the Arabian Sea, where the depth range of the OMZ is two times greater. The Bay of Bengal patterns may take on added significance as OMZs shoal globally.  相似文献   

2010-2011年胶州湾叶绿素a与环境因子的时空变化特征   总被引：2，自引：1，他引：1  

王玉珏  刘哲  张永  汪岷  刘东艳 《海洋学报》2015,37(4):103-116

2010年4、6、8、10月和2011年1、3月在胶州湾开展了6个航次的综合调查,研究了表层海水温度、盐度、营养盐和叶绿素a浓度的时空变化特征。调查期间,总无机氮(DIN)、磷酸盐(PO4)和硅酸盐(SiO3)多呈现东北部湾边缘高,而湾内和湾口低的空间分布特征。季节变化表明,DIN和PO4主要受养殖排放、河流径流输入和浮游植物生长消耗的影响,呈现初夏和秋季高,夏末和冬季低的特点;而SiO3主要受河流径流输入和浮游植物消耗的影响,呈现夏、秋高,而冬、春低的特点。营养盐浓度和结构分析表明,胶州湾存在PO4和SiO3的绝对和相对限制;SiO3限制尤其严重,是控制胶州湾浮游植物生长的主要环境因子。SiO3和PO4的限制主要表现在冬季,几乎遍布整个海湾;夏季降水可有效缓解海域的SiO3限制。叶绿素a浓度呈现春、夏季高,秋、冬季低的季节分布,温度、营养盐浓度与结构和季节性贝类养殖活动是控制胶州湾叶绿素a浓度时空分布的关键因素。  相似文献   

基于生态系统服务的海洋健康评估与调控:以莱州湾为例     

沈程程  郑伟  石洪华  丁德文  王宗灵 《海洋学报(英文版)》2015,34(12):61-66

近岸海域的生态系统管理,要求对海洋健康进行综合的评估以及对人工调控进行科学的指导,进而促进可持续发展。本文构建了定量化方法,用于评估当前的和近期的基于生态系统服务的海洋健康。以莱州湾为例的研究结果表明,当前的海洋健康指数分值为0.7856(总分为1.0);通过对负面压力进行不同强度的人工调控,得到近期海洋健康预计的变化范围为0.5551到0.8041。具体地说,本文评估得到当前的海洋健康主要表现为文化服务和供给服务基本优秀,而支持服务和调节服务不够良好。若不对持续增长的压力采取有效的调控措施,该近岸海域生态系统会在近期丧失部分支持服务和调节服务;若负面压力被完全控制,该近岸海域生态系统服务的分类等级会得到小幅提升。另外,应进一步加强对生态系统服务尤其是文化服务和调节服务的宣传教育。本文的分析过程和量化结果,为进一步指导人工调控提供了灵活的工具,有助于海岸带区域的生态系统管理。  相似文献   

Grain size composition and transport of sedimentary organic carbon in the Changjiang River (Yangtze River) Estuary and Hangzhou Bay and their adjacent waters     

ZHANG Weiyan  JIN Haiyan  YAO Xuying  JI Zhongqiang  ZHANG Xiaoyu  YU Xiaoguo  ZHANG Fuyuan  GAO Aigen 《海洋学报(英文版)》2015,34(10):46-56

Surface sediments from the Changjiang River(Yangtze River) Estuary,Hangzhou Bay,and their adjacent waters were analyzed for their grain size distribution,organic carbon(OC) concentration,and stable carbon isotope composition(δ13C).Based on this analysis,about 36 surface sediment samples were selected from various environments and separated into sand(0.250 mm,0.125–0.250 mm,0.063–0.125 mm) and silt(0.025–0.063 mm)fractions by wet-sieving fractionation methods,and further into silt-(0.004–0.025 mm) and clay-sized(0.004mm) fractions by centrifugal fractionation.Sediments of six grain size categories were analyzed for their OC andδ13C contents to explore the grain size composition and transport paths of sedimentary OC in the study area.From fine to coarse fractions,the OC content was 1.18%,0.51%,0.46%,0.42%,0.99%,and 0.48%,respectively,while theδ13C was –21.64‰,–22.03‰,–22.52‰,–22.46‰,–22.36‰,and –22.28‰,respectively.In each size category,the OC contribution was 42.96%,26.06%,9.82%,5.75%,7.09%,and 8.33%,respectively.The OC content in clay and fine silt fractions(0.025 mm) was about 69.02%.High OC concentrations were mainly found in offshore modern sediments in the northeast of the Changjiang River Estuary,in modern sediments in the lower estuary of the Changjiang River and Hangzhou Bay,and in Cyclonic Eddy modern sediments to the southwest of the Cheju Island.Integrating the distribution of terrestrial OC content of each grain size category with the δ13C of the bulk sediment indicated that the terrestrial organic material in the Changjiang River Estuary was transported seaward and dispersed to the Cyclonic Eddy modern sediments to the southwest of the Cheju Island via two pathways:one was a result of the Changjiang River Diluted Water(CDW) northeastward extending branch driven by the North Jiangsu Coastal Current and the Yellow Sea Coastal Current,while the other one was the result of the CDW southward extending branch driven by the Taiwan Warm Current.  相似文献   

Factors affecting local permit ownership in Bristol Bay     

《Marine Policy》2015

Since the first limited entry Bristol Bay drift and set gillnet permits were issued in 1975, many local residents have sold their permits to non-resident fishermen. Declining local permit ownership destabilizes the main economic base of the region. Previous studies have documented the decline of locally owned permits and have proposed social and economic hypotheses that could explain why local permit ownership is declining in limited entry fisheries in Alaska. To stem the outward flow of permits, the Bristol Bay Economic Development Corporation operates a Permit Loan Program to assist Bristol Bay watershed residents in buying permits. Despite its generous benefits, it has not reversed the decline in local permit ownership. This paper examines why residents enter or exit the fishery. Hypotheses on permit retention were tested through interviews with Bristol Bay fishery participants. Interviewees indicate stronger cultural and familial ties than economic factors to fishing. As local permit ownership has declined, these ties are being lost, leading to declining interest in the fishery. Commercial fishing is a competitive and costly enterprise. Successful participants in the fisheries, especially the drift gillnet fishery, are financially savvy with supplemental non-fishing income that outcompete residents by catching most of the fish. The Bristol Bay Economic Development Corporation Permit Loan Program appears unable to stop the local loss of permits. There are no obvious ways to expand local permit ownership and retaining local permits remains a major challenge for the region. However, it is important for local residents to participate in the fishery because it keeps communities economically and socially healthy, gives residents access to their local resources and strengthens their voice in managing their local resources.  相似文献   

2013年春季崂山湾浮游植物群落及其环境控制   总被引：4，自引：0，他引：4  

乔芮  栾青杉  王俊  袁伟  崔毅  孙坚强 《海洋科学》2015,39(7):13-21

2013 年春季(3、4、5 月)对崂山湾海域浮游植物群落及其理化环境进行了3 个航次的调查研究。共鉴定浮游植物40 属75 种, 硅藻是调查区主要的浮游植物类群; 浮游植物细胞丰度平均为1.27×10⁶个/m³,3 月份的平均丰度显著高于4、5 月份(P<0.01); 优势种主要为冰河拟星杆藻(Asterionopsis glacialis)、加拉星平藻(Asteroplanus karianus)、密联角毛藻(Chaetoceros densus)和夜光藻(Noctiluca scintillans), 浮游植物群落演替明显, 由3 月份硅藻控制逐步过渡到4、5 月份硅/甲藻共同控制; 相对较低的硝酸盐水平是导致4、5 月份浮游植物丰度显著低于3 月份的主要原因; 物种–环境数据的冗余分析(RDA)结果显示, 温度、硝酸盐含量是控制崂山湾春季浮游植物分布的重要环境因子。  相似文献   

基于GIS的近海剩余环境容量计算模型   总被引：1，自引：0，他引：1  

柯丽娜  王权明  徐丽雯  姜昕  杨山力 《海洋科学》2015,39(7):112-117

探讨一种基于GIS 克里格插值方法的剩余环境容量计算方法, 通过GIS 地统计分析插值模型将水质模拟问题转化为数学统计问题, 充分利用水质水体、沉积物监测数据, 采用克里格插值法对污染物浓度和水深在局部海域内进行插值, 将研究区域离散为一个个的均匀栅格单元, 比较每个单元污染物浓度与水质目标之间的差值, 从而估算得到研究海域的剩余环境容量。通过2009 年8 月锦州湾剩余环境容量的计算实例表明, 基于GIS 的剩余环境容量初步计算方法在资料缺乏地区是十分简便、有效的, 这为海域开发利用区环境管理与规划提供了参考。  相似文献   

辽东湾水体吸收系数区域性半分析反演算法     

苏园园  丘仲锋  张艳萍 《海洋科学》2015,39(4):73-81

水体吸收系数是影响水体光场分布的重要参数,在水色遥感探测中受到广泛关注。本文利用2012年9月辽东湾区域航次调查数据分析该区域水体各组分吸收系数的分布情况,结果表明,辽东湾水体中浮游植物含量相对较高。并利用该航次数据,建立了区域性半分析算法,该算法基于相邻波段间固有光学量的线性关系,首先通过遥感反射率反演得到550 nm波段的水体总吸收系数,再通过后向散射波段相关关系外推得到其他波段的总吸收系数。经独立测试数据检验,3个波段(412、443、550 nm)总吸收系数反演的平均相对误差分别为19.71%,17.99%,9.35%,说明区域性半分析算法能较好地估算研究区域的水体总吸收系数。本文还通过引入随机误差对算法稳定性进行了检验,结果表明算法具有较好的稳定性。  相似文献